U.S. patent application number 11/931842 was filed with the patent office on 2009-04-30 for system and method for wireless signal communication in an oil field environment.
This patent application is currently assigned to vMonitor, Inc. Invention is credited to Raed H. Abdallah.
Application Number | 20090110107 11/931842 |
Document ID | / |
Family ID | 40582821 |
Filed Date | 2009-04-30 |
United States Patent
Application |
20090110107 |
Kind Code |
A1 |
Abdallah; Raed H. |
April 30, 2009 |
SYSTEM AND METHOD FOR WIRELESS SIGNAL COMMUNICATION IN AN OIL FIELD
ENVIRONMENT
Abstract
A method is disclosed for transmitting data in a wireless oil
field environment, the method comprising sensing a signal change
rate for an input signal from an oil field apparatus; selecting a
real time transmission mode when the signal change rate is less
than a predetermined value; selecting a buffered data transmission
mode when the signal change rate is greater than or equal to the
predetermined value; and transmitting the data in the selected
transmission mode from a wireless oil field environment. A system
is disclosed for performing the method.
Inventors: |
Abdallah; Raed H.; (Houston,
TX) |
Correspondence
Address: |
G. Michael Roebuck, PC
FROST BANK BUILDING, 6750 WEST LOOP SOUTH, SUITE 920
BELLAIRE
TX
77401
US
|
Assignee: |
vMonitor, Inc
Houston
TX
|
Family ID: |
40582821 |
Appl. No.: |
11/931842 |
Filed: |
October 31, 2007 |
Current U.S.
Class: |
375/295 ;
340/855.4 |
Current CPC
Class: |
H04L 25/38 20130101;
E21B 47/13 20200501; H04L 25/0262 20130101 |
Class at
Publication: |
375/295 ;
340/855.4 |
International
Class: |
G01V 3/00 20060101
G01V003/00; H04L 27/00 20060101 H04L027/00 |
Claims
1. A method for transmitting data in a wireless oil field
environment, the method comprising: sensing a signal change rate
for an input signal from an oil field apparatus; and selecting a
real time transmission mode when the signal change rate is less
than a predetermined value; selecting a buffered data transmission
mode when the signal change rate is greater than or equal to the
predetermined value; and transmitting the data in the selected
transmission mode from a wireless oil field environment.
2. The method of claim 1, wherein the buffered data transmission
mode further comprises: sending once per period, a data buffer of N
data values representing the input signal when a condition is met;
and sending once per period a data buffer of changed data values
and a set of N bits indicating which of the N data values
correspond to the changed data values when the condition is not
met.
3. The method of claim 2, wherein the condition further comprises
data transmission buffer available space exceeding data buffer size
by a predetermined margin.
4. The method of claim 3, the method further comprising, dividing a
sampling duration into N intervals, wherein each of the N data
values corresponds to one of the N intervals.
5. The method of claim 3, wherein in the set of N bits, bits
representing a changed data value are set to one and all other bits
are set to zero.
6. The method of claim 4, wherein the number of intervals N is
increased as the signal change rate increases.
7. The method of claim 6, wherein the predetermined margin is
proportional to N.
8. The method of claim 2, wherein the data buffer further comprises
N start time values and N stop time values corresponding to the N
data values.
9. The method of claim 1, further comprising: receiving the data in
the selected transmission mode; outputting the received data as
output data, wherein the input data and the output data are signals
selected from the group consisting of digital, voltage and
current.
10. A system for transmitting data in a wireless oil field
environment, the system comprising: a processor in data
communication with a computer readable medium; a computer program
embedded in the computer readable medium, the computer program
comprising instructions to sense a signal change rate for an input
signal from an oil field apparatus, instructions to select a real
time transmission mode when the signal change rate is less than a
predetermined value and instructions to select a buffered data
transmission mode when the signal change rate is greater than or
equal to the predetermined value and instructions to transmit the
data in the selected transmission mode from a wireless oil field
environment.
11. The method of claim 10, wherein the buffered data transmission
mode further comprises instructions to send once per period, a data
buffer of N data values representing the input signal when a
condition is met and sending once per period a data buffer of
changed data values and a set of N bits indicating which of the N
data values correspond to the changed data values when the
condition is not met.
12. The system of claim 11, wherein the condition further comprises
data transmission buffer available space exceeding data buffer size
by a predetermined margin.
13. The system of claim 12, the computer program further comprising
instructions to divide a sampling duration into N intervals,
wherein each of the N data values corresponds to one of the N
intervals.
14. The system of claim 13, wherein in the set of N bits, bits
representing a changed data value are set to one and all other bits
are set to zero.
15. The system of claim 13, wherein the number of intervals N is
increased as the signal change rate increases.
16. The system of claim 15, wherein the predetermined margin is
proportional to N.
17. The system of claim 11, wherein the data buffer further
comprises N start time values and N stop time values corresponding
to the N data values.
18. The system of claim 11, the computer program further
comprising: instructions to receive the data in the selected
transmission mode; and instructions to output the received data as
output data, wherein the input data and the output data are signals
selected from the group consisting of digital, voltage and
current.
19. A data structure embedded in a computer readable medium, the
data structure comprising: a first field for containing data
indicative of available transmission buffer of space; and a second
field for containing data indicative of a predetermined margin by
which the available buffer space must exceed a data buffer size to
meet a condition.
20. The medium of claim 19, the data structure further comprising:
a third field for containing data indicative of a signal change
rate below which a real time transmission mode is selected and
above which a buffered transmission mode is selected.
Description
BACKGROUND
[0001] 1. Field of the Disclosure
[0002] The field of the present disclosure relates to wireless data
transmission in an oil field environment.
[0003] 2. Background
[0004] The exploitation of hydrocarbon reserves includes several
phases including production and processing at a well site. Well
site activities include monitoring of several parameters of the
well site to ensure safety at the site and surrounding areas and to
ensure the produced hydrocarbon products, either at the raw product
stage or during or after well site processing, have a desired
quality.
[0005] Information obtained by well site monitoring is used by well
site personnel and by off-site personnel and customers for various
purposes, including control of the well site and recording various
production and well site parameters.
SUMMARY
[0006] A method is disclosed for transmitting data in a wireless
oil field environment, the method comprising, sensing a signal
change rate for an input signal from an oil field apparatus;
selecting a real time transmission mode when the signal change rate
is less than a predetermined value; selecting a buffered data
transmission mode when the signal change rate is greater than or
equal to the predetermined value; and transmitting the data in the
selected transmission mode from a wireless oil field environment. A
system is disclosed for performing the method.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] For detailed understanding of the present disclosure,
references should be made to the following detailed description of
the several illustrative embodiments, taken in conjunction with the
accompanying drawings, in which like elements have been given like
numerals and wherein:
[0008] FIG. 1 is an illustration of a wireless transmitter and
receiver deployed in an oil field production well in an
illustrative embodiment;
[0009] FIG. 2 is a schematic depiction of an transmitter system
provided in an illustrative embodiment;
[0010] FIG. 3 is a schematic depiction of an receiver system
provided in an illustrative embodiment;
[0011] FIG. 4 is a schematic depiction of a replicated signal in
another illustrative embodiment;
[0012] FIG. 5 is a schematic depiction of a data structure provided
in another illustrative embodiment;
[0013] FIG. 6 is a schematic depiction of a data structure provided
in another illustrative embodiment; and
[0014] FIG. 7 is a flow chart of functions performed in another
illustrative embodiment; data
[0015] FIG. 8 is a depiction of data structure provided in a
illustrative embodiment.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0016] Portions of the present disclosure, detailed description and
claims may be presented in terms of logic, software or software
implemented aspects typically encoded on a variety of computer
readable media including, but not limited to, computer-readable
media, machine-readable media, program storage media or computer
program product. Such media may be handled, read, sensed and/or
interpreted by a computer or information processing device. Those
skilled in the art will appreciate that such media may take various
forms such as cards, tapes, magnetic disks, and optical disks.
Examples of magnetic disks include floppy disks and hard drives,
and examples of optical disks include compact disk read only memory
("CD-ROM") and digital versatile disc ("DVD"). It should be
understood that the given implementations are illustrative only and
do not limit the present invention.
[0017] Some portions of the present disclosure, detailed
description and claims use the term information, data, message, and
these terms may be used in the singular or plural form. The term
information as used herein refers to any information relating to
well site monitoring and may include any one or combination of
data, signal, message, command, and response, any of which may be
analog or digital and may be communicated by wireless or wired
transmission.
[0018] In a particular illustrative embodiment, one or more
wireless transmitters are coupled or connected to an analog input
or digital input device, such as an oil field apparatus such as a
pressure sensor, communicating data to one or more wireless
receivers connected to an analog output or digital output device.
The wireless transmitter and receiver can be housed in a package
suited or housing for industrial areas. The housing is a gas tight
box in one embodiment. In another embodiment the wireless
transmitter includes but is not limited to a main controller board,
one more digital input input/output (IO) channels, one more analog
input IO channels, a radio unit, and an antenna mounted to the
housing and a power source (i.e. battery pack). The wireless
receiver includes but is not limited to a main controller board
including a processor and a computer readable medium containing
data and a computer program, one more digital input IO channels,
one more analog input IO channels, a radio unit, an antenna mounted
on the housing and a power source (i.e., battery pack). In another
embodiment a system is provided having at least one
transmitter/receiver set, a number of transmitters communicating
with a single receiver set, two or more sets of any combination of
thereof.
[0019] A particular embodiment replaces cabling for applications
that use a high data rate sampling (1 to 1000 MHz per second or
more) using external or internal serial radio frequency (RF) radio
or transmission control protocol (TCP) wireless Radio. In these
high data rate applications substantially every change in value in
the data input to the transmitter from the source (e.g., oil field
apparatus) is detected, recorded and transmitted to the receiver
where the change is output to a transmitter output channel. The
output of the transmitter is received by a receiver system and
output in a prescribed protocol or data type (digital or analog).
Another particular embodiment detects and transmits substantially
every change in value from the input source. A particular
embodiment maintains the signal modulation width and preserves the
signal detected at the input source and reproduces input signal at
the output channel at the receiver system. There can be a delay in
time between when the input source detects the signal change and
when the receiver outputs the signal value.
[0020] A particular embodiment substantially optimizes data
communication between the transmitter and receiver to reduce data
traffic. In a particular embodiment, a wireless transmitter and
sensor are provided that read analog and digital data. The data
input to the transmitter is transmitted wirelessly to a wireless
receiver. In a particular embodiment, a main controller, radio, one
or more sensors (or one or more analog or digital input channels
connected to external sensors), a radio, an antenna, a battery pack
(optional can be powered by external source) and in a housing. A
wireless receiver is provided that receives the input signal from
one or more wireless transmitters. The wireless receiver provides a
main controller, a radio, one more analog or digital output
channels, a radio, an antenna, a battery pack (optional can be
powered by external source) and a housing.
[0021] In another embodiment, the input signal is read from the
wireless transmitter in different formats (i.e. 4-20 milliamps, 1-5
v, 0/1 digital input, etc). In another embodiment, as the wireless
transmitter sends the data to the wireless receiver the transmitter
designates the type of data transmitted (i.e. 4-20 milliamps, 1-5
v, 0/1 digital input, etc). In another embodiment, the wireless
receiver is configured to output the signal in any format desired
(i.e. 4-20 mA, 1-5 v, 0/1 digital input, etc). In another
embodiment the main controller unit for the transmitter is
configured for continuous reading (sampling up 1000 or more
readings per second) of one or more input channels. In another
embodiment, the main controller unit is configured to detect signal
changes in any of the input channels and immediately transmit the
new value to the wireless receiver. In another embodiment, the main
controller unit is configured to read incoming data from one or
more transmitters and immediately output the data to a designated
output channel.
[0022] In another embodiment, a main controller unit is configured
to transmit data at predefined period (normally 1 sec) to the
wireless receiver. Every 1 second (or whatever the defined period
is) any change in the input signal is detected and stored to
preserve the signal duration and signal value and substantially all
the changes in the input signal are stored in a transmission data
buffer. At the end of the transmit period all the changes in the
input signal along with the width of each change are transmitted to
the wireless receiver. In another embodiment, the main controller
unit is configured read to incoming buffered data in the
transmission data buffer and sequentially output the signal from
the incoming buffer data to the designated output channel for that
transmitter to preserve and enable replication of the signal width
and value.
[0023] In another embodiment, the transmitter reads incoming data
fast enough to ensure that the radio incoming transmission data
buffer does not over flow. One way to do this is to have a
dedicated thread that simply reads data from the incoming serial
buffer and moves the data to another data buffer so that other
threads (i.e., the outputting signal thread) to read it and perform
some action with it (i.e., output the data to the output channel).
In another embodiment, there is more than one of wireless receiver,
each of which receives data from one or more wireless transmitters.
In another embodiment, to reduce wireless traffic and wireless data
collisions, transmitter radios of different frequencies are
provided or radios with the same frequency but with different
communication channel settings are provided.
[0024] In another embodiment, a messaging protocol is provided and
used between the transmitter systems and receiver systems to
identify messages from the different transmitters/receivers, error
detection/correction, identify message types, pair input/output
channels, etc. The messaging protocol consists of a message header,
message body and message footer. In another embodiment, there are
two types of techniques or transmission mode used in signal
replicating and transmission. The first transmission mode is the
real time transmission mode that is utilized for low frequency
signals or signal change rates (for example, a signal change rate
less than 10 Hz per second) and other for high frequency signals or
signal change rate (for example, a signal change rate greater than
or equal to 10 Hz per second). The signal change rate at which
different transmission modes are selected can be higher than 10 Hz,
for example, instead of 10 Hz, another embodiment switches at 100
Hz and another embodiment switches transmission modes at 1000 Hz
and yet another embodiment switches transmission modes at 1 Kilo
Hz.
[0025] In low frequency applications the transmitter is
substantially continuously scanning the input channels for changes
in value. Whenever a change in the signal value is detected the
changed value is immediately transmitted to the receiver. At the
receiver the low frequency message reporting the changed value is
immediately output to the output channel. In high frequency
applications the transmitter continuously scans the input channels
for change in value. However instead of immediately transmitting
the value to the receiver system, the value is stored in a
transmission data buffer. After a predefined X time (can range from
1 sec to x minutes) the transmitter will send all the detected
signal changes in the data buffer to the receiver. To preserve data
integrity and signal width the time length for each signal or
changed a data value is transmitted as well.
[0026] At the receiver system, once the message is received the
receiver starts outputting the values as they are stored in the
transmitted data buffer. The receiver uses the time length
associated for each value to determine how long to wait before
outputting the next value in the data buffer. With this method
every x time or period the transmitter sends all the data
representing changes detected and the receiver uses a "play back"
technique to out put these data representing changed values to
reproduce the signals as detected at the transmitter. In another
embodiment, to preserve data integrity for high frequency signal
change rates a sampling duration, such as a 1 second sampling
duration, is divided into internals. In another embodiment them
number of internals is equal to the maximum number of scanning
channels available on the transmitter. Thus if the maximum scan
rate for channel is 500 samples per second then each sampling
duration of 1 second is divided into 500 internals. Each second (or
sampling duration) the transmitter transmits all changed data
values and a bit stream indicating intervals in which a value
change was detected. So if there was a change value during
intervals 5, 50, 100, 200, 311 of the 500 intervals during the
sampling duration, then a table of data is sent representing the N
bits and the changed values. The receiver outputs the value
received based on the bit marked interval. This way the input
signal width is preserved in the output signal.
[0027] In another embodiment, the transmitter system automatically
detects how fast the input value is changing and can auto switch
between the instantaneous messaging (slow frequency) and buffered
messaging (high frequency). In another embodiment, to cancel and
reduce the noise impact the transmitter system provides a signal
edge detection tolerance so it can detect and eliminate spurious,
noisy, bogus or fake signals which can over flow the communication
out put transmission channel if not detected. In another embodiment
the size of a transmission buffer is monitored and a transmission
mode selected based on avail able space in the transmission
buffer.
[0028] In another embodiment, a method is disclosed for
transmitting data in a wireless oil field environment, the method
comprising sensing a signal change rate for an input signal from an
oil field apparatus; selecting a real time transmission mode when
the signal change rate is less than a predetermined value;
selecting a buffered data transmission mode when the signal change
rate is greater than or equal to the predetermined value; and
transmitting the data in the selected transmission mode from a
wireless oil field environment. In another embodiment of the
method, the buffered data transmission mode further comprises
sending once per period, a data buffer of N data values
representing the input signal when a condition is met; and sending
once per period a data buffer of changed data values and a set of N
bits indicating which of the N data values correspond to the
changed data values when the condition is not met. In another
embodiment of the method the condition further comprises data
transmission buffer available space exceeding data buffer size by a
predetermined margin. The margin can be set to 50 percent or any
value from 1-100 percent, so that the available space in the
transmission buffer is 50 percent (or another set percentage)
larger than the data buffer size. The margin is be dynamically
adjusted based on the signal change rate.
[0029] In another embodiment of the method, the method further
comprising dividing a sampling duration into N intervals, wherein
each of the N data values corresponds to one of the N intervals. In
another embodiment of the method the set of N bits, bits
representing a changed data value are set to one and all other bits
are set to zero. In another embodiment of the method, the number of
intervals, N is increased as the signal change rate increases. In
another embodiment of the method, the predetermined margin is
proportional to N. In another embodiment of the method, the data
buffer further comprises N start time values and N stop time values
corresponding to the N data values. In another embodiment the
method further comprises receiving the data in the selected
transmission mode; and outputting the received data as output data,
wherein the input data and the output data are signals selected
from the group consisting of digital, village and current.
[0030] In another embodiment, a system is disclosed for
transmitting data in a wireless oil field environment, the system
comprising a processor in data communication with a computer
readable medium; a computer program embedded in the computer
readable medium, the computer program comprising instructions to
sense a signal change rate for an input signal from an oil field
apparatus, instructions to select a real time transmission mode
when the signal change rate is less than a predetermined value and
instructions to select a buffered data transmission mode when the
signal change rate is greater than or equal to the predetermined
value and instructions to transmit the data in the selected
transmission mode from a wireless oil field environment. In another
embodiment of the system, In another embodiment of the system, the
buffered data transmission mode further comprises instructions to
send once per period, a data buffer of N data values representing
the input signal when a condition is met and sending once per
period a data buffer of changed data values and a set of N bits
indicating which of the N data values correspond to the changed
data values when the condition is not met.
[0031] In another embodiment of the system, the condition further
comprises data transmission buffer available space exceeding data
buffer size by a predetermined margin. In another embodiment of the
system, the computer program further comprises instructions to
divide a sampling duration into N intervals, wherein each of the N
data values corresponds to one of the N intervals. In another
embodiment of the system, the set of N bits, bits representing a
changed data value are set to one and all other bits are set to
zero. In another embodiment of the system, the number of intervals,
N is increased as the signal change rate increases. In another
embodiment of the system, the predetermined margin is proportional
to N. In another embodiment of the system, the data buffer further
comprises N start time values and N stop time values corresponding
to the N data values. In another embodiment of the system, the
computer program further comprises instructions to receive the data
in the selected transmission mode; outputting the received data as
output data, wherein the input data and the output data are signals
selected from the group consisting of digital, voltage and
current.
[0032] Turning now to FIG. 1, FIG. 1 is an elevation view of a well
site 100 to illustrate a non-limiting example of a system according
to the disclosure. The site 100 as shown includes a conventional
well head 102 positioned at a producing well 104. The well 104 has
disposed therein a production tube 106, which has been shut in by a
barrier 108. The barrier 108 serves to isolate a lower portion of
the well from an upper portion. In one example, the barrier 108 may
be conventional packers.
[0033] The production tube 106 leads from within the well 104 to
the well head 102 where the production tube connects to a product
pipe 112. The product pipe 112, as shown, may lead to one or more
tanks 110. The product pipe may include several valves 128, 130 for
controlling fluid flow through the product pipe 112. The tank 110
may be used to temporarily store produced products. The product
tank 110 may include one or several output pipes as illustrated in
FIG. 1 by an upper output pipe 114 and a lower output pipe 116. The
upper output pipe 114 may be used for example to recover light oils
and gas from the tank 110, and the lower output pipe 116 may be
used to recover heavier oils from the tank 110. Where the well site
is a gas producing site, the tank 110 may be preceded by not-shown
processing and pressurizing structures and devices. The tank 110,
in the case of gas wells, may be a pressure vessel.
[0034] Continuing with FIG. 1, monitoring devices 118, 122, 124 and
126 are strategically located at several locations of the well site
100 to monitor any number of parameters relating to the produced
products and/or well site tools. A transmission system 200 is
included at each monitoring device. The monitoring devices can
include a battery operated camera 101 for transmitting wireless
video data to a receiving system. The camera stays in sleep mode
unless motion is detected in associated motion detection. Upon
detecting motion the camera wakes up, filing a predetermined video
data segment duration and transmits the video data to a receiving
system before going back to sleep. The monitoring devices may be in
communication with a receiving system 300 at a local node gateway
device 132 operating as a node controller. In several exemplary
embodiments, the local node device includes output control
interfaces coupled to well site tools such as the valves 128, 138
for controlling at least some operations at the well site. In a
particular illustrative embodiment each monitoring device can be
enclosed in a gas tight housing to prevent risk of an explosion due
to electronic energy or spark igniting explosive gases near a
monitored well. Each monitoring device can include one or more of a
processor, computer readable media such as computer memory,
database storage and a radio transceiver enclosed in the gas tight
housing.
[0035] Portions of the well site as indicated by dashed line 134
may be designated as a hazardous or explosive zone due to, among
other possible reasons, potentially hazardous or explosive gases or
other products being produced at a particular well site 100. In
some cases, the node controller 132 may be located outside of the
predetermined hazardous or explosive zone. The gas tight housing
reduces risk of explosions in the explosive zone.
[0036] Any number of useful monitoring devices may be employed at
the well site 100 and at any number of locations. Non-limiting
examples of monitoring devices and locations include one or more
sensors 118 disposed within the borehole of the well 104 for
monitoring down hole parameters of the well site. These down hole
sensors may be permanently or temporarily disposed within the well
104. The down hole sensors 118 may be coupled to the outside of the
production tube 106, to the inner flow channel of the production
tube 106, inside a wall of the production tube 106, to or within a
casing 120 or any combination of these or other possible down hole
locations.
[0037] In other non-limiting examples, any combination of surface
sensors may be used to monitor surface parameters of the well site
100. Surface sensors may include, for example, a sensor 122 for
monitoring parameters at the well head 102, a sensor 124 for
monitoring parameters in and/or along the surface production pipe
112, and a sensor 126 for monitoring parameters associated with the
storage tank 110. Each of the sensors 122, 124 and 126 may be a
single sensor or multiple sensors. Non-limiting examples of sensors
include absolute and differential pressure sensors, temperature
sensors, flow sensors, multi-phase sensors, optical sensors,
nuclear sensors, gas detectors, motion sensors, imaging sensors
such as video and/or still cameras or any combination of these and
other sensors useful for monitoring well site operations. Any or
all of these sensors may be analog or digital sensors. In the case
of analog sensors, analog to digital converters may be employed at
the well site or at the sensor location to aide in the transmission
and processing of information obtained by the sensors.
[0038] In several non-limiting examples, the local node controller
132 may be placed in long-range wireless communication with a
gateway device 136 for relaying information and messages to/from
remote users or system devices such as a Supervisory Control and
Data Acquisition (SCADA) system. In some cases it is desirable to
communicate between a node monitoring device and the gateway 136.
Therefore, the scope of the present disclosure includes
communicating information to and from a monitoring device, which
may be a sensor 122 or sensor cluster having a data communication
with a communication device 132. In an illustrative embodiment the
communication device 132 is a gateway, however, the communication
device may also be any device capable of receiving and temporarily
storing configuration message data in a mailbox for reading by
another device or retransmission to another device.
[0039] Turning now to FIG. 2, an illustrative embodiment of a
transmission system is depicted. As shown in FIG. 2, transmission
system 200 receives input from an analog device 202 in the form of
1 to 5 Volts or 4-20 milliamps. The analog input is provided by
analog input device 204. The system 200 also receives digital input
from a digital device 208 at digital input device 206. The system
also includes a main controller board 216 which includes a
processor and a computer readable medium 214 in which a set of
computer readable instructions are stored in the computer readable
medium for execution by the processor. The main controller board
and processor are in data communication with transmitter radio 218
which transmits signals via transmitter antenna 220. A power supply
or battery pack 212 is also incorporated into the system 200. An
industrial housing 210 is provided for housing and detecting the
transmitter system in a particular embodiment the housing 210 is a
gas tight box or operating in an explosive environment.
[0040] Turning now to FIG. 3, a receiver system 300 is illustrated
as provided in another illustrative embodiment. The receiver system
receives signals from the transmitter system 100 via antenna 320.
The antenna 320 is connected to a receiver radio 318 which is in
data communication with a main controller board on the receiver
system 300. The main controller board 316 includes a processor and
a computer readable medium or memory storage device 114. The main
controller board is in data communication with an analog output
tool which outputs a configurable signal to analog output device
302. Analog output device outputs an analog signal consisting of a
1-5 volts or 4-20 milliamps output signal. Additional ranges of
voltages and currents can also be used. The main controller board
is also in data communication with a digital output device 306
which outputs a digital data stream via a digital output device
308.
[0041] Turning now to FIG. 4, as shown in FIG. 4, a digital input
data stream or analog signal is illustrated by the series of pulses
402, 404, 406, 408, 410, 412, 414, 416, 418 and 420. The analog or
digital signals are received at the transmitter system 100 and
transmitted by the transmitter system 100 to receiver system 200.
The receiver system outputs the service of pulses is replicated by
the receiver which substantially matches the input data stream. The
output data stream is shown as a series of pulses 422, 424, 426,
428, 430, 432, 434, 436, 438 and 440.
[0042] Turning now to FIG. 5, in an alternative embodiment a data
structure is provided comprising data structure fields that retain
data that represent data stored in a data buffer. The data
structure represents a data buffer that comprises a data value for
each signal change detected at the input to the transmitter. It
another embodiment changed data values are stored in a data buffer
and transmitted from the transmission buffer by the transmitter
system to the receiver system. In a real-time transmission mode a
signal value start and stop time value and data value are
transmitted each time input signal change detection occurs. In a
buffered transmission mode, a signal start and stop time is
transmitted periodically.
[0043] As shown in FIG. 5, a data structure 500 represents the data
buffer. At 502 the data structure embedded in a computer readable
media, the data structure further includes a field for storing data
indicative of a time start for data value for signal value 1 504.
At 506 the data structure further includes field for storing data
indicative of a stop time value for signal value 1. Another
illustrative embodiment provides a data structure field for storing
data representing the data buffer containing a signal value for
each of a plurality of signal change values. In another particular
embodiment, each of the signal values 1-N are presented by data
values stored in the data structure. In another particular
embodiment, each of the signal values 1-N are represented by data
values stored in the fields in the data structure. In another
particular embodiment, each of the signal change values 1-N is
represented by data values stored in the data structure.
[0044] Turning now to FIG. 6 in another particular embodiment a
data structure is provided comprising a bit array representing bits
1 through N and a set of interval change values for intervals 1-N.
As shown in FIG. 6 a data structure 600 comprises a set of bits
610, 612, 614, 616, 618, 620, 622, 624, 626, 628, 630 and 632
representing and on off state for bits 1 through N. In another
particular embodiment the bit stream 1-N is presented in a bit
array that represents changed data values for intervals 1 through
N. The interval change data values corresponding to an interval
indicated with a bit set to 1, are stored in a bit position in the
bit array.
[0045] Turning now to FIG. 7, as shown in FIG. 7, a flowchart 700 a
series of functions performed in an illustrated embodiment are
depicted. At block 702 a frequency of signal change rate is
detected. If the signal change rate is less than a first
predetermined value, a real time transmission mode is selected at
block 704. In this case the illustrative embodiment proceeds to
block 706 and sends a data value in real time from the transmitter
system to the receiver system. And the process ends at terminal
714. If the signal change rate is less than the first predetermined
value and any buffered transmission mode is selected at block 708.
If they available transmission buffer size is greater than a second
predetermined value at block 710 then the illustrative embodiment
proceeds to block 716 and sends only changed data values in a
buffer along with a bit array indicating which intervals correspond
to the changed data value. If the available transmission buffer
size is less than or equal to the second predetermined value the
embodiment proceeds to block 712 and sends the buffered data to the
receiver system. The illustrative embodiment then proceeds to
terminal 714 and ends.
[0046] Turning now to FIG. 8, a data structure 800 embedded in a
computer readable medium is disclosed. A first field 802 is
disclosed for containing data indicative of available transmission
buffer space. A second field 804 is disclosed for containing data
indicative of a predetermined margin by which the available buffer
space must exceed a data buffer size to meet a condition. A third
field 806 is disclosed for containing data indicative of a signal
change rate below which a real time transmission mode is, selected
an above which a buffered transmission mode is selected.
[0047] The present disclosure is to be taken as illustrative rather
than as limiting the scope or nature of the claims below. Numerous
modifications and variations will become apparent to those skilled
in the art after studying the disclosure, including use of
equivalent functional and/or structural substitutes for elements
described herein, use of equivalent functional couplings for
couplings described herein, and/or use of equivalent functional
actions for actions described herein. Such insubstantial variations
are to be considered within the scope of the claims below.
[0048] Given the above disclosure of general concepts and specific
embodiments, the scope of protection is defined by the claims
appended hereto. The issued claims are not to be taken as limiting
Applicant's right to claim disclosed, but not yet literally claimed
subject matter by way of one or more further applications including
those filed pursuant to the laws of the United States and/or
international treaty.
* * * * *